The present invention relates a switching circuit for passing-through or cutting-off continuous or intermittent high voltage signals and a display device using same, and in particular to a switching circuit suitable for controlling a high voltage pulse signal by means of a low voltage signal and a display device using same.
Heretofore a switching circuit for passing-through or cutting-off an input signal by means of semiconductor elements is discussed in "How to use FETs" pp. 110-114, published by CQ Publishing Co. Ltd., 1983, in which a method is described, by which a small signal is imputted in the source of an MOS transistor and an output signal is taken out from the drain, whereby the potential of the body (substrate) is set with respect to the source or the drain so that the p-n junctions therebetween are never biased in the forward direction under any conditions and the signal conduction and cutting-off is controlled by the gate voltage.
However by the prior art technique no attention is paid to passing-through or cutting-off high voltage signals nor to utilizing a stray diode between the drain and the body.
A first object of the present invention is to provide a simple switching circuit utilizing a stray diode existing between the drain and the body of an MOS transistor.
A second object of the present invention is to provide a high voltage signal switching circuit, which controls particularly the passing-through and cutting-off of a high voltage signal by means of a low voltage signal.
A third object of the present invention is to provide a capacitive load driving device, which drives a capacitive load with a low electric power consumption, and a display device using same.